The invention relates to coking processes for upgrading atmospheric and vacuum residues and, more particularly, to an oil soluble coking process additive, and method for making and using same, which reduces or minimizes coke formation and enhances desired distillation reactions.
Coking is an increasingly important process whereby heavy petroleum fractions such as atmospheric residue, vacuum residue, high-boiling virgin or cracked petroleum residue and the like are efficiently converted to more desirable distillate products, along with a by-product of coke.
A number of coking methods are known in the art. For example, U.S. Pat. No. 4,305,809 to Chen et al. discloses one such method, as does U.S. Pat. No. 4,756,819 to Bousquet et al.
Although conventional coking processes do provide for an upgraded distillate product, it is of course desirable to reduce the amount of by-product coke which is formed during such processes.
It is therefore the primary object of the present invention to provide a coking method whereby coke production is minimized and distillate production is enhanced.
It is a further object of the present invention to provide an oil soluble additive for coking process feedstock which minimizes or reduces flocculation and which shows catalytic activity toward distillate forming reactions.
It is still another object of the present invention to provide a method for preparing such an oil soluble additive from starting materials which are inexpensive and readily available.
Other objects and advantages of the present invention will appear hereinbelow.
In accordance with the present invention, the foregoing objects and advantages are readily attained.
According to the invention, a method is provided for making an oil soluble coking process additive, which method comprises the steps of: providing a mixture of a metal salt in water wherein the metal salt contains a metal selected from the group consisting of alkali metals, alkaline earth metals and mixtures thereof; providing a heavy hydrocarbon; forming an emulsion of said mixture and said heavy hydrocarbon; heating said emulsion so as to dehydrate said emulsion and react said metal salt with components of said heavy hydrocarbon so as to provide a treated hydrocarbon containing an oil soluble organometallic compound, wherein said organometallic compound includes said metal and is stable at a temperature of at least about 300xc2x0 C.
In further accordance with the present invention, an additive for a coking feedstock is provided, which additive comprises: a hydrocarbon containing an oil soluble organometallic compound containing a metal selected from the group consisting of alkali metals, alkaline earth metals and mixtures thereof.
Still further in accordance with the present invention, a coking process is provided, which process comprises the steps of providing a heavy hydrocarbon feedstock containing an oil soluble organometallic compound containing a metal selected from the group consisting of alkali metals, alkaline earth metals and mixtures thereof; and subjecting said heavy hydrocarbon feedstock to coking conditions, whereby said organometallic compound acts as an anti-flocculent thereby minimizing coke formation.